The invention relates generally to a Radio Data System (RDS) receiver and, more particularly, to an RDS receiver with a memory which can be updated by inserting a chip card.
From the paper by Peter Brxc3xa4gas xe2x80x9cGuidance and Information Systems in the Motor Vehiclexe2x80x94A Contribution for the Improvement of Traffic Movement and of Traffic Safetyxe2x80x9d, journal xe2x80x9cInternational Trafficxe2x80x9d, book 5/85, a method for the route-selective reproduction of digitally coded traffic news is known. In which the traffic news itself is transmitted in code. Based on the coding, standard texts and place names will be called up, from which the traffic information is composed. From the DE-OS 35 36 820, a receiver for traffic messages can be understood, in which the local codes and the standard texts are stored in a read-only memory (ROM). This ROM thus forms a component part of the car radio and deciphers the transmitted codes and converts them into an intelligible language. For this purpose, the ROM has standard texts and local codes stored.
Another known car radio is the Blaupunkt Montreux RCR 30. This car radio has a decoder for digitally transmitted signals, which are sent out by a radio transmitter. The digitally transmitted signals in this radio are shown on a display unit. Furthermore, this car radio has a slot into which is inserted a chip card. The chip card contains a security code, which allows operation of the car radio only if the security code agrees with the security code stored on the chip card in the car radio. The chip card itself contains a resistance network, the value of which is interrogated by a computer in the car radio.
In contrast, the radio receiver in accordance with the invention, or the chip card in accordance with the invention, has the advantage that the data memory is easily exchangeable. This results in the radio receiver being adaptable in a particularly simple manner, to the linguistic aspects. It further opens up the possibility of taking into account the latest road conditions or local codes without opening the radio receiver, since it can happen during the lifetime of a radio receiver that place names are changed, and this can then be easily updated. A further advantage may be seen in the fact that even with a limited storage capacity, the radio can be used worldwide. By selecting suitable chip cards, it is after all possible to adapt the radio receiver individually to regional conditions. This makes it possible to manufacture one single radio receiver which does not require individual adaptations, specific to a particular country. It also allows the radio receiver to be manufactured such that it does not require the extensive memory.
It is of particular advantage to arrange the decoder and the evaluation unit for the traffic news on the chip card. This makes it possible for the radio receiver to become even cheaper, because the measures required for the evaluation of the traffic news do not have to be effected within the radio receiver, but are instead undertaken by a decoder and an evaluation circuit on the chip card. In particular, any further developments and improvements to be anticipated during the introductory phase are very easily realized by this measure, since only the chip card needs to be replaced. Another advantage is obtained by connecting the chip card with the radio receiver, via electrical contacts. This measure enables a safe transmission of the digital data. It is further advantageous to design the chip card such that it is withdrawable. This enables, on the one hand, a speedy replacement of the chip card, and, on the other hand, additional security can be obtained for the radio receiver, if the same can be operated only in conjunction with a security code on the chip card. Finally, the owner of a chip card can also use it in conjunction with other radio receivers, so that it is not necessary to have a separate chip card for each radio receiver. Furthermore, it is expedient to provide a voltage supply to the chip card via the radio receiver. This makes self-sufficient operation of the chip card possible, and no voltage sources are required in the chip card, which makes its manufacture simple and economic.
In its simplest version, the chip card for such a radio receiver contains a data memory with data of the vocabulary and the local code. In this case, the evaluation unit and the decoder must be accommodated in the radio receiver. In a further embodiment design of the chip card, it is of advantage to integrate the evaluation unit for the traffic news on the chip card. There are then no alterations required in relation to a commercial radio receiver, apart from the fact that the indicating device and the acoustic output must be suitably prepared for receiving information which is output by the chip card. It is expedient that the chip card is configured such that it has electrical contacts on its front side. This provides for a particularly reliable contact of the chip card with the radio receiver. Naturally, contactless transmission routes, for example, inductively, with high frequency, are possible. The chip card will also contain a security code to good advantage, which makes operation of the car radio possible only if the code stored on the chip card agrees with the code stored in the radio receiver.